Upgrading RAM on my Dell PC?

[flobadob]

From another question I got this link http://www.crucial.co...ension%203100&Cat=RAM and video https://www.youtube.com/embed/mGTT0Vcy0E4

But is it really as easy to do this as it looks? My PC has 504MB RAM and I'm thinking of buying the 2x1GB cards. Also does removing the old RAM cards mean you lose any data from the PC?

[flobadob]

Thanks.